US1022707A - Solenoid-controller. - Google Patents

Description

P. W. SMITH. SOLENOID CONTROLLER.

APPLICATION FILED 11211.5, 1910.

1,022,707. Y Patented Apr 9,1912.

f. M 4 a g I am dtto'wmgyjg L p STATES PATENT OFFICE.

mN-K W. SMITH, OF WESTFIELD, NEW JERSEY, ASSIGNOR TO SUNIDH ELECTBIG COMPANY, OF NEW YORK, N. Y., AGOBPORAT'ION OF NEW YORK.

SOLENOID-CONTROLLER.

Specification of Letters Patent.

Patented Apr. 9, 1912 Application filed April 5, 1910. Serial No. 553,546.

To all whom it may concern I Be it known that I, FRANK W. SMITH, a

citizen of the United States, and resident of the town of \Vestfield, county of Union, and State of'New Jersey, have invented certainnew and useful Im rovements in Solenoid-Controllers, of which the following is a specification, reference being had therein to'the accompan ing drawing, in which- Figure 1 is a iagrammatic view of a motor, a motor starting solenoid, and the controller device.

In starting electric motors having great 'inertia to overcome, and requiring a considerable current over-load to move them, it has been the practlce, heretofore, to 1nsert in the motor circuit enough resistance to prevent the burning out of the motor eration, w ereby the resistance will be gr'ad 1 the motor isreduced and consequently the armature when the current is applied, and

then cutting out the resistance by some form of a paratus having a step-by-step' opuall reduced as the motorspeed is accelerate ,"and the inertia of the mass to be moved by the motor is overcome, or the motor load otherwise reduced.

It is the main object of thisinvention' to provide a solenoid controlling means by means of which when the motor circuit is com leted the movement of the solenoid core will retarded or stopped until the load on amount. of current taken by the motor is also reduced, the solenoid core being permitted to complete its movement only when the current taken by the motor hasbeen reduced to the desired extent. It is, of course,

obvious that the amount of current taken I force. 1

e the op of course, obvious that there may be many;

by\the"'motor may .be reduced in yarious ways. lVhen the inertia of the load is over come and the motor has increasedits speed the load thereon is reduced, and consequently the amount of current taken by it is mrrespondingly reduced. It is also ob vious that as the speed of the motorincreases there is a reduction in the amount of current taken by the motor by reason of the .back pressure or counter-electromotive Itis the ob'ect of this invention totake advantage of t is reductionv in current taken by the motor in whatever way it may be brought about, for the purpose of control ration of the solenoid, auditis,

variations in the specific apparatus forearrying this invention into effect, and I therefore desire it understood that I am not tc be limited to the precise construction shown and described, except as the same may be the core whereby said core will move into the coil slowly, and at the desired speed.

Pivoted to the solenoid frame are two contact levers 9 and 9 which carry contacts 10 and 10 at their upper ends adapted to engage the fixed contact 11, this latter con tact being electrically connected to the source of supply and to the solenoid coil.

The contact levers are electrically connected to pole 1 of the vmotor armature, as will be more fully hereinafter described.

Carried by the solenoid core at. its lower end is a frame 12, and in said frame are arranged rollers 13. These rollers are arranged to engage'cams 14; and 15 formed on the inner sides of the contact levers at'the lower ends-thereof. The cam M is located near the end of its contact lever, while the cam 15 is some distance above the cam 14:,

whereby one of the rollers 13 will first contact with the cam'l i, and thereby bring contact 10 into engagement with the con tact 11, the cam 15 being operated upon at a later period, as will be more fully herein after set fort-in Contact lever 9 is connected to one polel of the motor armature through the resistance coil .16 anda retarding coil 17, said 'recarding coil being of large capacity topermit the motor current to pass therethrough. The contact lever 9 is electrically connected to the samepole of the motor armatnreas lever 9, as clearly shown in the diagram. The fields of the motor are connected through a shunt 18, with the lever 9 Above the retarding coil 17 is pivoted a horizontal lever 19, said lever being providedwith a threaded arm 20 inwhich is its arranged a counterbalancing weight 21. The Hi said lever is drawn downwardlyaway from the balanced lever 'by it, "on the motor,

the contact or stop 22, the solenoid coil cir cuit will be through said resistance, said cirquit being broken between the stop 22 and The operation of this apparatus may be briefly described as follows: When the switch 24 is closed, current passes through the balanced lever 19,-stop 22 and the solenoid coil, but not through the resistance coil 25. By means of the weight 21 the lever 19 and the core 23 are nicely balanced so that said lever will be normally in contact with the stop 22, but may be readily drawn from stop 22 by means of the coil 17 and the core 23. Upon the completion of the circuit through the solenoid coil, the'core 5 will be' drawn'upwardly, said upward movement being retarded to the desired extent by the dash pot 7. 'When the roller 13 contacts with the cam 14, the upper end of the lever 9 will be thrown inwardly to bring'the contact 10 into engagement with the rigid contact 11. Current will then flow from the lever 9.through the resistance coil 16, the retarding coil 17 to the pole 1 of the motor armature. When current passes through the retarding coil- 17, the core or plunger 23 will be drawn downwardly into said coil thereby breaking the solenoid coil circuit at the stop 22, and causing said circuit to be completed through t-he resistance 25. The resistance 25 is suificient to reduce the effective pull of the solenoid coil, and to thereby. prevent further upward movement of the solenoid core. The core and the sliding frame 12 will, therefore, be held stationary after the said frame has been raised above the cam 14, the outwardly projecting part'of the cam 14 engaging under the end bar of frame 12 and assisting the coil in maintaining the core in its stationary intermediate posit-ion. This condition of the apparatus will be maintained until the load on the motor has been reduced, and consequently the amount of current taken by the motor is correspondingly reduced. This reduction in current may be brought about by the motor over coming the inertia of the mass to be moved or by the actual reduction of the load or by the counter-electromotive force developed by the motor. It is clear that as the current flowing throu h the motor is reduced the pull of pleted by the contacts first the coil 1 will be correspondingly reduced, and when said pull has been lowered to the desired extent. it will failto overcome the weight 21,- and said weight will then throw lever 19 into engagement with stop 22, thereby cutting out the resistance 25 and permitting the full current to flow through the solenoid coil. As soon as this occurs the solenoid coil will complete its upward movement, thereby causing contact lever 9 to swing in-; wardly and bring contact 10 into engagement with the fixed contact 11. The motor circuit will then be completed through said lever 9, and directly to pole 1" of the armature motor, thereb cutting out the resistance coil 16 and t e retarding coil 17, and supplying the full current to the motor.

From the foregoin tarding coil 17 will gold thelever 19 away from the contact 22 until the current flowing to the motor and through the coil 17 has been reduced sufiiciently to so diminish the pull of the coil 17 that the weight 21 will overcome it and swing the arm 19 into engagement with the contact 22. It is manifestsolenoid will be inthat the operation of the termittent, and that the final step or movement thereof will be dependent upon the reduction of the current taken by the motor. It is also clear that the interval between the completion of the solenoid coil circuitand the cutting out of the resistance in the motor circuit will depend entirely upon the time required to reduce the current flowin to the motor through retarding coil 17 su ciently to release the core 23.

It will, of course, be understood that the solenoid retarding device may be employed in many ways, and on any desired form of solenoid.

It is also clear that the motor circuit may be completed through the retarding coil in any suitable manner, the arrangement shown in the drawings being merely by way of illustration. 1

It will, of course, be understood that by varying the position of the weight 21 on the arm 20 the amount of pull required to .move the arm 19 from the stop 22 may be varied, and consequently the amountof reduction in current flowing through said coil to bring about the release the core 23 will be correspondingly varied.

Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent is: 4

1. A controller comprising a solenoid coil, means connectin said solenoid coil .directly in circuit with t e source of supply, a core for said coil, a pair of contacts brbught toit is clear that the re- I gether bythe initial movement of said core,

a motor, a motorcircu'it adapted to be como erated by the solenoid core, a resistancean a controlling coil in said motor circuit, a

movable core excess of current is flowing through said motor circuit, means to return said solenoid coil circuit to its normal condition whenrthe current flowing through the motor circuit is reduced, and. to thereby permit the solenoid core to complete its movement, and

contacts operated by said core as it cont pletes its movement to out the resistance and the controllin coil from the motor circuit.

2. A solenoid controller comprising asolenoid coil, a single core movable into and out of said solenoid coil, a pair of contacts arranged to be closed or opened by the movements of said core, an operating circuit arranged to be completed by the said pair of contacts, a resistance and a controlling coil in said circuit, a core movable into and out of said controlling coil, means moved by said core for cutting resistance into the solenoid coilcircuit, means tending to return said movable means to its normal position to cut resistance out of the solenoid coil circuit and operating against the pull of the controlling coil, a second pair of contacts arranged -to be closed by the further movement of the solenoid core, this latter pair of contacts also completing the operatmg circuit. and cutting out the resistance and the controlling coil, thereby reventing the subsequent re-in'troduction o the re. sistance into the solenoid coil circuit. o

3. A solenoid controller comprisih asolenoid coil, a single reciprocablecore or said coil,:'acircuit for said coil, a pair. of contacts arranged to be closed by the movement of said core, a motor circuit adapted to be com p'leted by the said pair of contacts, a resistance anda controlling coil in said motor circuit, a reciprocable core in said controlling coil, movable means operated by said core for cutting resistance into the solenoid coil circuit, said means tending always to.) return'to its normal position, saidcontrolling coil operating under anvexcess of cur-' rent to place resistance in the solenoidcoil circuit and operating whenthe current .in the motor circuit is sufliciently reduced to cut the resistance from the solenoid circuit thereby permitting the solenoid core to continue its movement, another pair of contacts adapted to be operated by the subsequent movement of the solenoid core, this latter pair of contacts completing the circuit through the motor direct and perinanently cutting out the resistance and the controlling coil of the motor, circuit.

4. A solenoid controller comprising a solenoid coil, a .core movable into and out of said .coil, contacts adapted to, be closed by said core at'diflierent points in its travel to close an electric circuit, and means in said circuit controlled by the movement of the solenoid core for neutralizing the pull of said coil tothereby arrest the movement of the core before it has completed its movement, said meansoperating upon a reduc tion of current in the circuit controlled by the solenoid to restore the solenoid to its normal act-ion.

5. The combination of a motor, a'solenoid coil, a circuit for said coil including means for opening and closing said circuit,

a core movable into and out of said coil,

' 6 A solenoid controller comprising a sole noid coil, a circuit for said solen id coil, a reclprocable'core movable into and out ofsaidcoil, a pair of contacts arranged to be brought together by the initial movement of -said core into the coil, a motor circuit adaptedto be completed when the saidpair of contacts are brought together by the said core, a resistance and a controlling coil in said motor circuit, a movable core for said controlling coil, meansin the solenoid coil circuit ,and connected to the core of the controlling coil to place resistance r in the solenoid coil circuit when an excess of current is flowing through the motor circuit said means returning said coil circuit to its normal condition when the current -flowing through the 'motor circuit is sufiibrought together by this second movement of the solenoid core said contacts completing the -motor circuit direct and/cutting out the resistance and the controlling coil and thereby, permanently cutting out the resistance from the solenoid coil circuit.

Intestimony whereof I hereunto aifix my signature in the presence of two witnesses this 1st day of April, 1910.

FRANK w. SMITH.

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